Limit switch connector

ABSTRACT

A thermocouple energized safety control having a housing enclosing a safety valve unit, an electrical terminal extending from said unit through a housing wall and terminating in a recess, a closure plate for the recess having a threaded opening therein to receive the terminals of a concentric lead type of thermocouple, a cup-shaped insulator member surrounding a slotted portion of the terminal, and a transversely slotted, cup-shaped electrical conductor member engageable by the central terminal of the thermocouple leads so that a first wire from a limit switch may be clamped between the valve unit terminal and the insulator member and a second wire from the limit switch may be clamped between the two cup-shaped members, to place the limit switch in series with the safety valve unit and the thermocouple.

United States Patent [72] Inventor Frederik J. Ages Los Angeles, Calif.[21] AppLNo. 866,331 [22] Filed Oct. 14, 1969 [45] Patented June 1, 197173] Assignee Honeywell, lnc.

Minneapolis, Minn.

[54] LIMIT SWITCH CONNECTOR 6 Claims, 2 Drawing Figs.

[52] US. Cl 137/66, 126/351, 317/123, 339/174 [51] int. Cl ..ll01h 47/22[50] Field of Search 126/351; 339/99, 174; 137/65, 66

[56] References Cited UNITED STATES PATENTS 3,467,893 9/1969 Jackson eta1. 126/351X Primary Examiner-William F. ODea Assistant ExqminerRichardGerard Attorneys-Lamont B. Kootz and Alan M. Staubly ABSTRACT: Athermocouple energized safety control having a housing enclosing asafety valve unit, an electrical terminal extending from said unitthrough a housing wall and terminating in a recess, a closure plate forthe recess having a threaded opening therein to receive the terminals ofa concentric lead type of thermocouple, a cup-shaped insulator membersurrounding a slotted portion of the terminal, and a transverselyslotted, cup-shaped electrical conductor membe'rjehgageable by thecentral terminal of the thermocouple leads that a first wire from alimit switch may be clamped between the valve unit terminal and theinsulator member and a second wire from the limit switch may be clampedbetween the two cup-shaped members, to place the limit switch in serieswith the safety valve unit and the thermocouple.

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II ml PATENTEU JUN 1 I97! FIG.

INVENIOR.

FREDERIK J. AGES ATTORNEY.

- LIMIT SWITCH CONNECTOR The invention relates to a manifold valve ofthe type'which is adapted to control the flow of gas to a water heater.Such valves usually include a rod and tube actuated thermostat valve, amanual plug valve, a safety valve energized by a thermocouple responsiveto the presence of a pilot burner flame and a highJimit switch in seriescircuit with the thermocouple and safety valve wherein the high-limitswitch is located to sense the water temperature. More particularly, theinvention is directed to the particular coupling between the high-limitswitch and the safety valve unit and the thermocouple.

FIG. 1 of the drawing is a fragmentary and somewhat schematic view ofthe invention; and

FIG. 2 is a cross section of the coupling elements shown at right angleto the elements as viewed in FIG. 1.

The reference numeral 11 designates the housing of the manifold valvewhich has a valve seat 12 for the safety valve 13, has an opening 14through which the supporting means for the valve unit extends and has arecess 15 in which the coupling means for the limit switch 16 andthermocouple 17 is located. A power unit 19, which is adapted to beenergized by the thermocouple when the thermocouple senses a flame 18afrom a pilot burner 18, is of conventional construction. lt is supportedin the housing 11 by an insulating sleevelike member 20 which surroundsa central connector 21 to insulate and connect a coil 19a to a headedterminal portion 210. The insulating member is illustrated as being heldin the opening 14 by means of a nut 22 of insulating material threadedonto the member 20. Connector 2! also has a slotted boss 21b extendinginto the recess 15 for the reception of the bared end 230 of a lead wire23 from high-limit switch 16. A cupshaped insulator member 24 has anannular flange 240 that bears against the bared wire 23a'to clamp itagainst the head 21a. The boss 21b fits in the cavity of the member 24.A second cup-shaped electrical conductor 25 has diametrically opposedslots 25a and an inwardly struck abutment portion 25b which leaves arecess or socket 250 in the opposite face thereof for the reception of ahead 26a of central thermocouple lead 26. A second bared end portion 27aof second lead 27 from the high-limit switch is clamped between theouter surface of the cup-shaped member 24 and the abutment portion 25band the inner ends of the slots 25a.

The thermocouple 17 is adapted to be electrically connected to thehigh-limit switch 16 by threading the conventional connector nut 28 intoa closing plate 29 for the cavity 15, so as to bias the head 26a intoengagement with the member 25, bias the member 25 against wire 27a, andto connect the switch 16 to the terminal 21 by having the same forcebias the insulator member 24 against the wire 23a, which, in turn, isbiased against the head portion 210. As coil 19a is grounded at 19b tothe metallic housing of the unit 19, the grounding of the outer lead 30from the thermocouple to the housing 11, through nut 28 and plate 29,completes the electrical circuit between the thermocouple, thehigh-limit switch and the coil.

It is thus seen that with the safety valve 13 opened by a conventionalmanual operator for the manifold valve and the pilot burner ignited andhaving a flame playing on the thennocouple 17, current will flow fromthe thennocouple 17 through the central lead 26 to the connector member25, through the lead 27 to the high-limit switch, back through the lead23 to central terminal 21 of the power unit, through the coil 19a of thepower unit, through the valve body including plate 29 to the clampingnut 28, and outer lead 30 back to the thermocouple. As long as there iscurrent flowing to the coil 19a, the armature will be held and the valve13 connected thereto kept in an open position. Should either the pilotflame 18a become extinguished or the water temperature surrounding thehigh-limit switch 16 approach the boiling temperature so as to open theswitch, the current flow to the coil will cease and cause the valve 13to close under the bias of its return spring 13a. It is thus seen that acompact and easy to assemble terminal arrangement is provided forconnecting a hi h-limit switch into the circuit of athermocouple-energize safety valve that will obviously provide reliableoperation.

The embodiments of the invention in which I claim an exclusive propertyor right are defined as follows:

1. In a thermocouple-energized gas flow control device including ahousing therefor, the combination comprising headed electrical terminalmeans extending through a wall of said housing with the head thereofresting in the bottom of a recess in said housing, insulation meanselectrically separating said terminal means from said housing, said headhaving an axially extending and transversely slotted boss of smallerdiameter than said head and shaped to receive a first wire therein, acup-shaped insulating means having an inside cavity adapted to receivesaid boss and to press said wire against said head, a cup-shapedelectrical conductor means having a transverse slot through thesidewalls thereof for the reception of a second wire and having aninside cavity adapted to receive said cupshaped insulating means andhaving abutment means thereon adapted to press said second wire againstsaid insulating means, and a wall member closing said recess and havinga threaded opening therein in axial alignment with said conductor meansand positioned so that upon threading the nut of the connector terminalsof a conventional concentric leads type of thermocouple into saidthreaded opening the central terminal head of said connector terminalswill clamp said second wire between said cup-shaped connector means andsaid cupshaped insulating means and will clamp said first wire betweensaid cup-shaped insulating means and said headed electrical terminalmeans.

2. A control device as defined in claim 1 wherein said wires are thebared ends of lead wires connected to a temperatureresponsive high-limitswitch.

3. A control device as defined in claim 2 wherein said lead wires extendthrough an opening in a sidewall of said recess.

4. A control device as defined in claim 1 wherein said cupshapedinsulating means has an annular flange around the open end thereof forengagement with said first wire.

5. A control device as defined in claim 4 wherein said cupshapedelectrical conductor means has an inwardly struck closed end portionthat internally provides a small area portion for engagement with saidsecond wire and an external socket portion for the reception of thecentral terminal head of said connector terminals of the thermocoupleleads.

6., A control device as defined in claim I in combination with a safetyvalve means operably connected to said terminal means.

1. In a thermocouple-energized gas flow control device including ahousing therefor, the combination comprising headed electrical terminalmeans extending through a wall of said housing with the head thereofresting in the bottom of a recess in said housing, insulation meanselectrically separating said terminal means from said housing, said headhaving an axially extending and transversely slotted boss of smallerdiameter than said head and shaped to receive a first wire therein, acup-shaped insulating means having an inside cavity adapted to receivesaid boss and to press said wire against said head, a cup-shapedelectrical conductor means having a transverse slot through thesidewalls thereof for the reception of a second wire and having aninside cavity adapted to receive said cup-shaped insulating means andhaving abutment means thereon adapted to press said second wire againstsaid insulating means, and a wall member closing said recess and havinga threaded opening therein in axial alignment with said conductor meansand positioned so that upon threading the nut of the connector terminalsof a conventional concentric leads type of thermocouple into saidthreaded opening the central terminal head of said connector terminalswill clamp said second wire between said cup-shaped connector means andsaid cup-shaped insulating means and will clamp said first wire betweensaid cupshaped insulating means and said headed electrical terminalmeans.
 2. A control device as defined in claim 1 wherein said wires arethe bared ends of lead wires connected to a temperature-responsivehigh-limit switch.
 3. A control device as defined in claim 2 whereinsaid lead wires extend through an opening in a sidewall of said recess.4. A control device as defined in claim 1 wherein said cup-shapedinsulating means has an annular flange around the open end thereof forengagement with said first wire.
 5. A control device as defined in claim4 wherein said cup-shaped electrical conductor means has an inwardlystruck closed end portion that internally provides a small area portionfor engagement with said second wire and an external socket portiOn forthe reception of the central terminal head of said connector terminalsof the thermocouple leads.
 6. A control device as defined in claim 1 incombination with a safety valve means operably connected to saidterminal means.